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<span id="Using-fast-enumeration"></span><div class="header">
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Next: <a href="c99_002dlike-fast-enumeration-syntax.html" accesskey="n" rel="next">c99-like fast enumeration syntax</a>, Up: <a href="Fast-enumeration.html" accesskey="u" rel="up">Fast enumeration</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Indices.html" title="Index" rel="index">Index</a>]</p>
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<hr>
<span id="Using-Fast-Enumeration"></span><h4 class="subsection">8.9.1 Using Fast Enumeration</h4>

<p>GNU Objective-C provides support for the fast enumeration syntax:
</p>
<div class="example">
<pre class="example">  id array = &hellip;;
  id object;

  for (object in array)
  {
    /* Do something with 'object' */
  }
</pre></div>

<p><code>array</code> needs to be an Objective-C object (usually a collection
object, for example an array, a dictionary or a set) which implements
the &ldquo;Fast Enumeration Protocol&rdquo; (see below).  If you are using a
Foundation library such as GNUstep Base or Apple Cocoa Foundation, all
collection objects in the library implement this protocol and can be
used in this way.
</p>
<p>The code above would iterate over all objects in <code>array</code>.  For
each of them, it assigns it to <code>object</code>, then executes the
<code>Do something with 'object'</code> statements.
</p>
<p>Here is a fully worked-out example using a Foundation library (which
provides the implementation of <code>NSArray</code>, <code>NSString</code> and
<code>NSLog</code>):
</p>
<div class="example">
<pre class="example">  NSArray *array = [NSArray arrayWithObjects: @&quot;1&quot;, @&quot;2&quot;, @&quot;3&quot;, nil];
  NSString *object;

  for (object in array)
    NSLog (@&quot;Iterating over %@&quot;, object);
</pre></div>





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